But this process can not take place on an integrated circuit since all transistors are fabricated on the same piece of silicon. This is one of the major drawn back of an integrated circuit compare to a discrete circuit.
All components on the silicone dice are formed by a droplet of chemical (very much like inkjet printer printing on paper). This fabrication process can not create parts like the 1% tolerant metal film resistor, or the super stable silver mica capacitor (please see table above to compare how discrete parts are different to their integrated substitute) Since they are all connected (hence integrated) they can not be individually tested and matched.
In an IC opamp the conductor layer that connects all the parts is formed by a layer of aluminium vapour that is thinner than the water vapour left on foggy windscreen. This poor conductor is the silent killer to musical texture.
The close proximity of components also poses a problem for audio signals, where that delicate signal that music lovers pursue, will be masked by EMI noise.
In the end, the consumer is getting an opamp that is built with a bunch of second grade parts that is unable to yield the best results, connected via a thin layer of aluminium foil.
An IC opamp is nothing more than a cost cutting substitute in audio application which we hate with a passion!